2026/02/28 by Anonymous, Shengtao Jiang, Steven R. White +2
Physics and Astronomy · #cond-mat.str-el
paper · pdf · doi:10.1103/zmnz-tkq2
published as Phys. Rev. Lett. 137, 056703 (2026) · 5+5+9 pages, 3+3+9 figures
openalex publication_date 2026/06/16 · openalex created_date 2026/06/17 · arxiv created 2026/07/28 · arxiv updated 2026/07/30 · openalex updated_date 2026/07/30
Previous studies of the S=1/2 triangular-lattice J1--J2 Heisenberg antiferromagnet have inferred the existence of a non-magnetic ground-state phase for an intermediate range of J2, but disagree concerning whether it is a gapped ℤ2 quantum spin liquid (QSL), a gapless (Dirac) QSL, or a weakly symmetry-broken phase. Using an improved dynamical density-matrix renormalization group method, we investigate the relevant intermediate J2 regime for cylinders with circumferences from 6 to 9. Depending on the initial state and boundary conditions, we find two \it distinct variational states. The higher energy state is consistent with a Dirac QSL. In the lower-energy state, both the static and dynamical properties are qualitatively similar to the magnetically ordered state at J2=0, suggestive of either a weakly magnetically ordered non-QSL or a gapped QSL proximate to a continuous transition to such an ordered state.